C++ namespace mangling: bug or me being stupid?

[kinke via Digitalmars-d-learn]

That's a mangling compression scheme (possibly tunable via gcc 
options), from 
https://github.com/gchatelet/gcc_cpp_mangling_documentation:
> To save space a compression scheme is used where symbols that 
> appears multiple times are then substituted by an item from the 
> sequence : S_, S0_, S1_, S2_, etc ...

As to nested C++ namespaces - `extern(C++, ns1) { ... extern(C++, 
ns2) { ... } }` should work in a single D file.